I currently setup my monitors with "Nvidia Xserver Settings"-GUI applet. I can see monitors fine, and set them up. But they do not work properly.

When using right monitor as main monitor (as it is with my setup), my left monitor is blank, only with task bar and normal-cursor, black desktop, If I try to open something to the left monitor (from task bar), it opens to the right monitor, right monitor works perfectly.

EDIT: this was the case in 18.1 [or 17.3], on 18.3 left monitor is black, and only cursor visible.

when I flip around ( with "Nvidia Xserver Settings"-GUI applet.) --> left (VGA1) to screen 0 and Right (DVI) to screen 1, things are reversed, the DVI is not recognized (by xrandr), and the left VGA monitor activates normally, right stays "blank" (picture later in the post)

It seems that second monitor output is always lost somewhere in xrandr, you can see the ones not connected, but not the connected (screen 1).

So --> How do I force VGA (screen 1) active, when DVI (screen 0) is main monitor?

I had similar issue with Ubuntu earlier on (14.04 perhaps?) And that is why I changed to Mint. In Mint 17.0, double monitors work out of the box, but I want to upgrade.
It does not help using different proprietary driver, or newest kernel. I have all updates installed right now.

And I DO need two separate x-screens for my setup, need to be able separately turn cubes

PS: I am collecting data all over the internet, and adding it to here, even if I sort this out on my own, others can read this and get the help they need.

Last edited by Janiporo on Sat Dec 16, 2017 2:04 pm, edited 7 times in total.

Now I removed the VGA-monitor, and installed DVI-monitor. (so now both monitors are DVI, and on the same graphics card, of course). Then also reinstalled operating system, but no, other monitor stays black, except for mouse cursor.

What can I do wake the other desktop?

Another thing is weird, if I try to open firefox to the second monitor, both start blinking fast in turns, and I can see the firefox started there, but there is no simultaneous picture on both monitors.

i just recently had an episode with my gtx 460. I had a 24" benq hooked up to hdmi, and a 22" dell hooked up with vga through a dvi adapter. the dell was stuck at 1024x768 even though it was supposed to be 1680 x 1050/ I had to research the dell monitor to get the correct hotizontal and vertical refresh hertz rates and open the xorg as admin located in etc/...11 and manually edit both refresh rates to the correct values. this worked for me....hope this helps. that refresh rate has to be right or all kinds of things go awry